INTENTIONAL SPINS


Chapter 4—Slow Flight, Stalls, and Spins
Table of Contents Introduction Slow Flight Flight at Less than Cruise Airspeeds Flight at Minimum Controllable Airspeed Stalls Recognition of Stalls Fundamentals of Stall Recovery Use of Ailerons/Rudder in Stall Recovery Stall Characteristics Approaches to Stalls (Imminent Stalls)—Power-On or Power-Off Full Stalls Power-Off Full Stalls Power-On Secondary Stall Accelerated Stalls Cross-Control Stall Elevator Trim Stall Spins Spin Procedures Entry Phase Incipient Phase Developed Phase Recovery Phase Intentional Spins Weight and Balance Requirements	INTENTIONAL SPINS The intentional spinning of an airplane, for which the spin maneuver is not specifically approved, is NOT authorized by this handbook or by the Code of Federal Regulations. The official sources for determining if the spin maneuver IS APPROVED or NOT APPROVED for a specific airplane are: Type Certificate Data Sheets or the Aircraft Specifications. The limitation section of the FAA-approved AFM/POH. The limitation sections may provide additional specific requirements for spin authorization, such as limiting gross weight, CG range, and amount of fuel. On a placard located in clear view of the pilot in the airplane, NO ACROBATIC MANEUVERS INCLUDING SPINS APPROVED. In airplanes placarded against spins, there is no assurance that recovery from a fully developed spin is possible. There are occurrences involving airplanes wherein spin restrictions are intentionally ignored by some pilots. Despite the installation of placards prohibiting intentional spins in these airplanes, a number of pilots, and some flight instructors, attempt to justify the maneuver, rationalizing that the spin restriction results merely because of a “technicality” in the airworthiness standards. Some pilots reason that the airplane was spin tested during its certification process and, therefore, no problem should result from demonstrating or practicing spins. However, those pilots overlook the fact that a normal category airplane certification only requires the airplane recover from a one-turn spin in not more than one additional turn or 3 seconds, whichever takes longer. This same test of controllability can also be used in certificating an airplane in the Utility category (14 CFR section 23.221 (b)). The point is that 360° of rotation (one-turn spin) does not provide a stabilized spin. If the airplane’s controllability has not been explored by the engineering test pilot beyond the certification requirements, prolonged spins (inadvertent or intentional) in that airplane place an operating pilot in an unexplored flight situation. Recovery may be difficult or impossible. In 14 CFR part 23, “Airworthiness Standards: Normal, Utility, Acrobatic, and Commuter Category Airplanes,” there are no requirements for investigation of controllability in a true spinning condition for the Normal category airplanes. The one-turn “margin of safety” is essentially a check of the airplane’s controllability in a delayed recovery from a stall. Therefore, in airplanes placarded against spins there is absolutely no assurance whatever that recovery from a fully developed spin is possible under any circumstances. The pilot of an airplane placarded against intentional spins should assume that the airplane may well become uncontrollable in a spin . Previous \| Next
Copyright 2012 PED Publication

Chapter 4—Slow Flight, Stalls, and Spins

Table of Contents
Introduction
Slow Flight
    Flight at Less than Cruise Airspeeds
    Flight at Minimum Controllable Airspeed
Stalls
    Recognition of Stalls
    Fundamentals of Stall Recovery
    Use of Ailerons/Rudder in Stall Recovery
    Stall Characteristics
    Approaches to Stalls (Imminent Stalls)—Power-On or Power-Off
    Full Stalls Power-Off
    Full Stalls Power-On
    Secondary Stall
    Accelerated Stalls
    Cross-Control Stall
    Elevator Trim Stall
Spins
    Spin Procedures
        Entry Phase
        Incipient Phase
        Developed Phase
        Recovery Phase
Intentional Spins
    Weight and Balance Requirements

INTENTIONAL SPINS

The intentional spinning of an airplane, for which the spin maneuver is not specifically approved, is NOT authorized by this handbook or by the Code of Federal Regulations. The official sources for determining if the spin maneuver IS APPROVED or NOT APPROVED for a specific airplane are:

Type Certificate Data Sheets or the Aircraft Specifications. The limitation section of the FAA-approved AFM/POH. The limitation sections may provide additional specific requirements for spin authorization, such as limiting gross weight, CG range, and amount of fuel. On a placard located in clear view of the pilot in the airplane, NO ACROBATIC MANEUVERS INCLUDING SPINS APPROVED.

In airplanes placarded against spins, there is no assurance that recovery from a fully developed spin is possible. There are occurrences involving airplanes wherein spin restrictions are intentionally ignored by some pilots. Despite the installation of placards prohibiting intentional spins in these airplanes, a number of pilots, and some flight instructors, attempt to justify the maneuver, rationalizing that the spin restriction results merely because of a “technicality” in the airworthiness standards.

Some pilots reason that the airplane was spin tested during its certification process and, therefore, no problem should result from demonstrating or practicing spins. However, those pilots overlook the fact that a normal category airplane certification only requires the airplane recover from a one-turn spin in not more than one additional turn or 3 seconds, whichever takes longer. This same test of controllability can also be used in certificating an airplane in the Utility category (14 CFR section 23.221 (b)).

The point is that 360° of rotation (one-turn spin) does not provide a stabilized spin. If the airplane’s controllability has not been explored by the engineering test pilot beyond the certification requirements, prolonged spins (inadvertent or intentional) in that airplane place an operating pilot in an unexplored flight situation. Recovery may be difficult or impossible.

In 14 CFR part 23, “Airworthiness Standards: Normal, Utility, Acrobatic, and Commuter Category Airplanes,” there are no requirements for investigation of controllability in a true spinning condition for the Normal category airplanes. The one-turn “margin of safety” is essentially a check of the airplane’s controllability in a delayed recovery from a stall. Therefore, in airplanes placarded against spins there is absolutely no assurance whatever that recovery from a fully developed spin is possible under any circumstances.

The pilot of an airplane placarded against intentional spins should assume that the airplane may well become uncontrollable in a spin

.

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